Gas water heater

ABSTRACT

A gas-operated water heater comprises a housing and an upright open-ended mixing tube defining a combustion chamber in the housing. The combustion chamber has gas burners, and the combustion product gases are drawn into the mixing tube by lowering of pressure therein caused by directing a spray of finely-divided water particles down the tube. Heat exchange between the combustion gases and the water takes place in the tube, and both water and gases flow out at the lower end of the tube.

United States Patent Denis GAS WATER HEATER [72] Inventor: Andre Denis, 23 Rue de Coq., Marseille,

France [22] Filed: May 19, 1970 [21] Appl. No.: 38,776

[52] U.S. Cl ..126/350 [51] lnt.Cl ..F24h 4/00 [58] Field of Search ..126/350, 359 56 References Cited UNITED STATES PATENTS 2,921,004 1/1960 Wood ..l26/350 x 940,240 11/1909 Duryea.... ...l26/350 3,331,366 7/1967 Sullivan ..l26/350 3,204,629 9/1965 Newton, Jr.. ...l26/350 UX 3,291,119 12/1966 Sullivan.... ..l26/350 3,326,202 Sullivan ..126/359 3,672,350 June 27, 1972 3,386,436 6/1968 Miyahara 126/359 FOREIGN PATENTS OR APPLICATIONS 448,398 5/1948 Canada 126/359 takes place in the tube, and both water and gases flow out at the lower end of the tube.

1 Claim, 1 Drawing Figure (L1 I 1/! I) 11/11/11 11/! I/IIIII/IIIII/ III IIIIIII/I I1 11/ PKTENTEDJUM? r972 ZQ E 7A GAS WATER HEATER The invention relates to a gas water-heater which operates by direct thermal exchange.

It is designed in particular to produce hot water in the open air or in adequately ventilated placed, such as for water-heating installations at swimming baths, ornamental pools and the like.

Known devices of this type, such as feed-water heaters or boilers, use a heater body one face of which is contacted by gas coming from a burner, and the other face by the liquid to be heated; in the case of gas burners, the types known as immersion heaters are also used.

The consequence is that the heater bodies and other indirect heating systems cause scaling. Similarly, the superpressure devices on immersion heaters do not provide all the desired working reliability, while in any case the expenditure of calories does not correspond to the required efiiciency.

The device in accordance with the present invention enables these disadvantages to be avoided; it eliminates the heater body and the consequent risk of scaling, as well as the immersion heater superpressure devices, allowing direct heating of the liquid by hot gases and using up the fuel's full calorific value, while the flow of the liquid stream evacuates the spent gases, and at the same time close contact with the finely divided water provides perfectly homogeneous heat exchange.

In the accompanying drawing, given as a non-limiting example of one form of construction of the invention, the device is shown as a whole, in vertical section.

The device consists of a pump 1 which sucks in the water to be heated and sends it up into a sprinkler rack 2 which, by means of distribution nozzles, separates the stream of water into finely divided particles. The atomized liquid falls by gravity into the mixing tube 3 which has a larger diameter than is theoretically needed to accommodate the flow of the water alone, thus creating a depression in this collector.

The gas is burnt at a plurality of burners, after having been previously mixed with air entering through intakes 4 in direct communication with the outside atmosphere. This air/gas mixture is burnt in a combustion chamber 5 fonned by a housing 8 and the mixture communicates directly with the top opening of the mixing tube 3. A secondary air intake 6 in the housing 8 opens into the combustion chamber 5 and ensures complete combustion.

The lighting of the burner can be synchronized, by means of a control device, with the water intake in the rack 2, and obtained by means of a pilot light or other known safety system providing full control of the heater.

The products of combustion, during firing, are sucked out by the lowering of pressure caused by the flow of atomized liquid through the rack 2.

This suction causes direct mixing of the atomized liquid and the combustion products and ensures perfect exchange of calories for homogeneous heating of the liquid, so that the combustion products have substantially lost their heat by the time that they emerge.

The heated water and combustion product gases come out of the tube 3, and the gases escape into the atmosphere and the water is ready for use. Efficiency is distinctly high, with a considerably saving in fuel.

I claim:

1. A gas-operated water heater comprising: a housing, an upright mixing tube disposed partially within and partially outside said housing, having an open upper end within said housing and serving to define therein an open-ended combustion chamber, said housing having means for inlet of gas-air mixture and for burning said mixture in the combustion chamber around said tube, a water-spraying device situated in the top of the housing and positioned to direct a downward spray of finely-divided water particles into the open upper end of the mixing tube and along the mixing tube, the cross-section of the mixing tube being greater than that required to accommodate the flow of water particles such that a lowering of pressure in the mixing tube causes the combustion product gases to be drawn upward around and downward into the mixing tube and to contact the water directly therein for exchange of heat therewith and to be exhausted concurrently from the housing through the tube downwardly together with the water. 

1. A gas-operated water heater comprising: a housing, an upright mixing tube disposed partially within and partially outside said housing, having an open upper end within said housing and serving to define therein an open-ended combustion chamber, said housing having means for inlet of gas-air mixture and for burning said mixture in the combustion chamber around said tube, a waterspraying device situated in the top of the housing and positioned to direct a downward spray of finely-divided water particles into the open upper end of the mixing tube and along the mixing tube, the cross-section of the mixing tube being greater than that required to accommodate the flow of water particles such that a lowering of pressure in the mixing tube causes the combustion product gases to be drawn upward around and downward into the mixing tube and to contact the water directly therein for exchange of heat therewith and to be exhausted concurrently from the housing through the tube downwardly together with the water. 